Question

In the Kibble–Zurek mechanism, causally disconnected domains undergo this process independently, and the resulting defect density scales with some power of the quench rate. A type of this process occurs when the probability distribution of overlap between different equilibrium configurations is no longer a delta function. In the 2D XY model, this process does [emphasize] not (-5[1])occur as pairs of topological defects unbind and free defects proliferate, because the spin-spin correlations vanish algebraically. This process is forbidden in low-dimensional (-5[1])systems by the Mermin–Wagner (10[1]-5[1])theorem. (10[3]-5[2])Phase transitions (10[1])from a fluid to a solid are accompanied by this process, since the system is no longer translation-invariant. (10[2])A form of this process (10[1])is accompanied by the creation of Nambu–Goldstone (10[1])bosons. (10[2])For 10 points, in the Higgs (-5[1])mechanism, particles acquire (10[1])mass when what process occurs (10[1])spontaneously? (10[2])■END■ (10[1]0[1])

ANSWER: symmetry breaking [or equivalents that use a word form of “break,” like a system experiencing broken symmetries; accept explicit, spontaneous, continuous, global, or local symmetry breaking; after “overlap” is read; accept replica symmetry breaking; prompt on phase transitions until “not” is read; until “defect density” is read, prompt on descriptions of the formation of topological defects or creation of topological defects by asking “defects form at the boundaries of domains for which what process has had a different outcome?”] (The second sentence refers to replica symmetry breaking. The third sentence refers to the Berezinskii–Kosterlitz–Thouless transition.)
<Physics>
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Summary

2023 ACF Nationals04/22/2023Y2176%0%29%107.88

Buzzes

PlayerTeamOpponentBuzz PositionValue
Arya KarthikGeorgia Tech ADuke A55-5
Vincent DuNorth Carolina AJohns Hopkins A78-5
Adam FineChicago ARutgers A82-5
Tim MorrisonStanford AGeorgia Tech B8210
Geoffrey WuColumbia AMcGill A83-5
Pranav SivaramOhio State ARutgers B83-5
Matthew LehmannWUSTL AIndiana A8310
Geoffrey ChenCornell AUC Berkeley A8310
Leo LawFlorida APurdue A8310
Noah ChenColumbia BYale B8510
Connor BlakeChicago CMichigan A10310
JD KrothIowa State AImperial A10310
Anson BernsBrown AClaremont A10810
Dan NiCornell BMinnesota B11510
Alex SchmidtPenn State AIllinois A11610
Katherine LeiMIT AFlorida B11610
Ian ChowToronto ASouth Carolina A122-5
Daniel MaYale AWUSTL B12510
Maxwell YeMinnesota APenn A13010
Mazin OmerHarvard AVanderbilt A13110
Isaac MammelMaryland AHouston A13110
Simon GorbatyDuke AGeorgia Tech A13210
Joelle SmartRutgers AChicago A1320